prepare-commit-msg.hook

#!/bin/bash

old_commit_msg="$(cat ${1})"
echo -n "" > "${1}"

if [[ ${old_commit_msg} != "mrgpkg: "* ]]
then
  # Check for new PKGBUILDs
  for path in $(git diff --name-only --cached --diff-filter=A); do
      if [[ "${path}" =~ .*/PKGBUILD$ ]]; then
          (
              source "${path}"
              : ${pkgbase:=${pkgname}}
              echo -e "addpkg: ${pkgbase} ${epoch:+${epoch}:}${pkgver}-${pkgrel}\n" >> "${1}"
          )
      fi
  done

  # Check for updated PKGBUILDs
  for path in $(git diff --name-only --cached --diff-filter=M); do
      if [[ "${path}" =~ .*/PKGBUILD$ ]]; then
          (
              source "${path}"
              : ${pkgbase:=${pkgname}}
              echo -e "upgpkg: ${pkgbase} ${epoch:+${epoch}:}${pkgver}-${pkgrel}\n" >> "${1}"

              # If the pkgrel is "1" and there is no VCS pkgver function (or there is one, but the git revision is "0"), assume a new version.
              [[ $pkgver =~ .+\.r([0-9]+)\..+ ]]
              [[ "${pkgrel}" = "1" && ( $(type -t pkgver) != "function" || ${BASH_REMATCH[1]} = 0 ) ]] && echo -e "Upstream Release: ${pkgname} ${pkgver}\n" >> "${1}"
          )
      fi
  done

  # Check for deleted PKGBUILDs
  for path in $(git diff --name-only --cached --diff-filter=D); do
      if [[ "${path}" =~ .*/PKGBUILD$ ]]; then
          echo -e "delpkg: ${path%/PKGBUILD}\n" >> "${1}"
      fi
  done
fi

echo "${old_commit_msg}" >> "${1}"